Jimi Hendrix had a lot to say in 1968, when he released Electric Ladyland, the third and final album with the Jimi Hendrix Experience. You can hear it in the sprawling double-record set's free-form jams, dizzying psych-rock freak-outs and occasional unevenness.

The period surrounding the album was a busy and productive one for Hendrix, who'd never release another studio record before his death two years later. For years, material recorded right before, during and right after the Electric Ladyland sessions has found its way onto posthumous collections.

Add Electric Ladyland: 50th Anniversary Deluxe Edition to that list.

The four-disc set includes a remastered version of the original 16-track album, a surround-sound mix on Blu-ray, a disc of previously unreleased demos and alternate takes and a concert CD that showcases just how powerful the trio of Hendrix, Mitch Mitchell and Noel Redding could be outside the studio.

The centerpiece of the box is Electric Ladyland itself, a still-stunning collection of studio-enhanced oddities, loose jam sessions and that breathtaking cover of Bob Dylan's "All Along the Watchtower." The best songs -- "Crosstown Traffic," "Voodoo Chile," "Voodoo Child (Slight Return)" and "Watchtower" -- manage to spin blues, pop, soul and rock into era-defining anthems that sweep past their genres into something more original and timeless.

Some of it's messy, and some of it can sound like psychedelic nonsense today. But there's no denying the pull of Hendrix's guitar and vision, folded into even sharper focus as he produced himself for the first time. It's Hendrix's most personal album, and a celebration of the studio and its limitless possibilities.

The disc of demos shows just how far the songs developed once Mitchell, Redding and more instruments entered the proceedings. Early skeletal takes of "Voodoo Chile" and "Long Hot Summer Night," featuring just Hendrix and his guitar, possess little of the dynamic and energy that make the finished band versions so enthralling. Songs that didn't make the final cut -- like "Angel" and "Snowballs at My Window" -- are a little more interesting in this solo setting, mainly because we don't get to hear them fleshed out on the box.

The live set -- recorded at the Hollywood Bowl on Sept. 14, 1968, about a month before Electric Ladyland's release -- contains only one song from the album, but it's a highlight of the show: a soaring eight-minute "Voodoo Child (Slight Return)." The rest of the previously unreleased tracks includes usual Experience concert songs like "Red House," "Foxey Lady" and "Purple Haze," all played with fiery intensity and no small amount of period heaviness.

These two CDs reveal a fuller picture of Electric Ladyland's achievements, and just how much work went into shaping the songs into ear-opening sonic landscapes with engineer Eddie Kramer. Check out "1983 ... (A Merman I Should Turn to Be)," which may be Hendrix's most epic recording, as layer after layer of feedback, manipulated to sound like seagulls, and backward guitars and flutes are unpeeled over 13 mind-blowing minutes. It's still quite a trip, half a century later.

All this experimentation came at a price, though. The Experience splintered during the sessions and broke up the following year. Hendrix split with his longtime manager. And he eventually found his way to a new trio that scaled back some of Electric Ladyland's ambitions. In a way, this 50th Anniversary Deluxe Edition marks the end of one glorious era and the beginning of the next, mostly unrealized one. Even if some of it seems unnecessary -- the demos offer few revelations, the concert becomes a noisy blur by the end -- at least the pieces fall together. Electric Ladyland still sounds like a singular triumph.

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